Alignment Control Research Articles

Hydrogel-polyurethane fiber composites with enhanced microarchitectural control for heart valve replacement.

Polymeric heart valves offer the potential to overcome the limited durability of tissue based bioprosthetic valves and the need for anticoagulant therapy of mechanical valve replacement options. However, developing a single-phase material with requisite biological properties and target mechanical properties remains a challenge. In this study, a composite heart valve material was developed where an electrospun mesh provides tunable mechanical properties and a hydrogel coating confers an antifouling surface for thromboresistance. Key biological responses were evaluated in comparison to glutaraldehyde-fixed pericardium. Platelet and bacterial attachment were reduced by 38% and 98%, respectively, as compared to pericardium that demonstrated the antifouling nature of the hydrogel coating. There was also a notable reduction (59%) in the calcification of the composite material as compared to pericardium. A custom 3D-printed hydrogel coating setup was developed to make valve composites for device-level hemodynamic testing. Regurgitation fraction (9.6 ± 1.8%) and effective orifice area (1.52 ± 0.34 cm2 ) met ISO 5840-2:2021 requirements. Additionally, the mean pressure gradient was comparable to current clinical bioprosthetic heart valves demonstrating preliminary efficacy. Although the hemodynamic properties are promising, it is anticipated that the random microarchitecture will result in suboptimal strain fields and peak stresses that may accelerate leaflet fatigue and degeneration. Previous computational work has demonstrated that bioinspired fiber microarchitectures can improve strain homogeneity of valve materials toward improving durability. To this end, we developed advanced electrospinning methodologies to achieve polyurethane fiber microarchitectures that mimic or exceed the physiological ranges of alignment, tortuosity, and curvilinearity present in the native valve. Control of fiber alignment from a random fiber orientation at a normalized orientation index (NOI) 14.2 ± 6.9% to highly aligned fibers at a NOI of 85.1 ± 1.4%. was achieved through increasing mandrel rotational velocity. Fiber tortuosity and curvilinearity in the range of native valve features were introduced through a post-spinning annealing process and fiber collection on a conical mandrel geometry, respectively. Overall, these studies demonstrate the potential of hydrogel-polyurethane fiber composite as a heart valve material. Future studies will utilize the developed advanced electrospinning methodologies in combination with model-directed fabrication toward optimizing durability as a function of fiber microarchitecture.

A Novel 2D/3D X-ray Microscopy Alignment and Inspection Solution for Thermocompression Bonding (TCB) in a Highly Integrated Flip Chip Fan-Out Wafer Level Package (FO-WLP)

As packaging drives to extend the capabilities of Moore’s Law via heterogenous integration, numerous bonding technologies have emerged as potential pathways, allowing for integration of both a variety of devices in the lateral space as well as vertical integration of chips via stacking. As vertical integration on interposer becomes more complex due to shrinking CDs and increasing die layers, alignment and shape control in the bonding process becomes critical. Thermocompression bonding (TCB) is particularly well-suited for larger die, where localized reflow allows a better control of chip gap height and tilt throughout the bonding process. TCB systems require both high accuracy and repeatability in all dimensions to provide a reliable system in package. While a 2D system can provide a plan view assessment of a single bond layer between two chips, it falls short in characterizing the critical z-dimension in a highly integrated chip stacking scenario. Therefore a robust solution is needed for both system alignment validation in the x,y plane as well as a capability to explore gap height and bump quality/buried issues in high aspect ratio TSV. This paper will explore an x-ray application of a stacked 15-layer die-to-interposer structure to qualitatively validate overall health of the TSV (bond, pad, fill) via a nondestructive volumetric method as well as quantitatively evaluate stacked die for via/ball/pad alignment to determine overall alignment shift during the bonding process. In the test vehicle for a flip chip FO-WLP process flow first presented by IMEC, a silicon (Si) bridge is utilized to connect the logic and through-package via dies with a bump pitch of 20µm for the logic die interconnect. This is done by carefully aligning the logic dies on the carrier and then placing the through-package dies aligned to the carrier and logic dies. In the final step, a high accuracy placement and stacking TCB tool attaches the Si bridge. To perform an accurate assessment for bump alignment and bond quality, an initial high-resolution 3D x-ray scan is performed on a 1.5mm3 region of interest with over 2,000 individual projections at a 1.4µm voxel resolution with a 4x objective, taking approximately two hours. The dataset is put through a deep-learning algorithm which generates an AI model. This model is then applied to a faster scan of 15 minutes with a 1.4µm voxel resolution for the same field of view (FOV) on a nearby array and the data is collected and processed. To verify alignment of the entire sample, data is collected on the tightest pitch (in this case 20µm) oriented in both the vertical (x) and horizontal (y) plane in the through-silicon via (TSV) region. The z-plane is analyzed and processed by computer vision algorithms, and individual interconnects are then quantified and sorted for solder height (z), width (x,y) and TSV misalignment (deviation from expected center, x1y1 → x2y2). To validate the model, a high-resolution uncorrected 20h scan and a 15min scan based on deep learning are collected for the same region of interest (ROI). The data is comparable. Furthermore, the global misalignment data between both datasets demonstrates similar misalignment propagating through the 15-layer stack.

Parking precise alignment control and cotransporter system for rice harvester and transporter

In autonomous rice harvesting, the use of transporters to assist rice transportation is an effective way to improve efficiency. However, nonlinear systems, such as double Hydraulic Static Transmission (HST)-driven tracked rice harvesters and transporters, make it challenging to control the precise parallel parking alignment during transportation, often leading to rice loss and potential safety hazards. To address this issue, this study established a geometric cotransporter model and used a preset path to decouple a two-dimensional control problem into two sets of one-dimensional controls. Dynamic and kinematic models of the longitudinal drive and steering systems were analyzed. Based on the identified longitudinal drive system transfer function, a predictive model was constructed to predict and compensate for the parking slip caused by system inertia. It was combined with the integrator wind-up protection to improve the pure tracking method and eliminate or reduce system errors in path tracking. A parallel parking alignment control system was designed using these two methods, and comparative experiments were conducted on the road surface. The results demonstrate that the compensated predictor (CP) longitudinal control improves the alignment accuracy compared with the proportional differential (PD) controller, whereas the Improved Pure-Pursuit Control (IPPC) path-tracking slightly enhances the tracking accuracy compared with proportional integral (PI). Moreover, a field-autonomous rice-harvesting cotransporter experiment showed that the longitudinal alignment accuracy of the designed system was less than 0.2 m. The lateral alignment accuracy was less than 0.1 m.

Clinical validation of the ‘C-arm rotational view (CARV)’: study protocol of a prospective randomised controlled trial

IntroductionRotational malalignment occurs in up to 30% of cases after intramedullary nailing of tibial shaft fractures. The aim of this study is to assess the clinical feasibility of a newly...

Objective assessment of eye alignment and disparity-driven vergence in Parkinson's disease.

Self-reported diplopia is described in up to one-third of Parkinson's disease (PD) patients. The purpose of our study was to expand our understanding of the mechanistic underpinnings of diplopia in PD. We hypothesize that the time-based control of eye alignment and increased eye deviation under binocular viewing will be related to the fusion-initiating and fusion-maintaining component deficits of disparity-driven vergence in PD. We used high-resolution video-oculography to measure eye alignment under binocular and monocular viewing and disparity-driven vergence in 33 PD and 10 age-matched healthy participants. We computed eye deviation and time-based control of eye alignment, occurrence of conjugate saccadic eye movements, latency and gain of vergence (fusion initiation), and variance of eye position at the end of dynamic vergence (fusion maintenance). We categorized PD subjects into three groups, considering their time-based control of eye alignment as compared to healthy controls in binocular viewing. Group 1 = 45% had good control and spent >80% of the time when the eyes were well-aligned, Group 2 = 26% had intermediate control and spent <80% but greater >5% of the time when the eyes were well-aligned, and Group 3 = 29% had very poor control with increased eye deviation majority of the times (<5% of the time when the eyes were well-aligned). All three groups exhibited greater eye deviation under monocular viewing than controls. PD subjects exhibited fusion-initiating and fusion-maintaining vergence deficits (prolonged latencies, reduced vergence gain, increased variance of fusion-maintaining component) with a greater probability of saccadic movements than controls. Group 2 and Group 3 subjects were more likely to exhibit failure to initiate vergence (>20%) than Group 1 (13%) and controls (0%) trials. No significant difference was found in the Unified Parkinson's Disease Rating Scale (UPDRS-a tool to measure the severity of PD) values between the three PD groups (Group 1 = 33.69 ± 14.22, Group 2 = 38.43 ± 22.61, and Group 3 = 23.44 ± 1, p > 0.05). The majority of PD subjects within our cohort had binocular dysfunction with increased eye deviation under monocular viewing and disparity-driven vergence deficits. PD subjects with intermediate or poor control of eye deviation under binocular viewing had greater fusion-initiating and fusion-maintaining vergence deficits. The study highlights the importance of assessing binocular dysfunction in PD subjects independent of the severity of motor symptoms.

Gate-electric-field and magnetic-field control of versatile topological phases in a semi-magnetic topological insulator

Surface states of a topological insulator demonstrate interesting quantum phenomena, such as the quantum anomalous Hall (QAH) effect and the quantum magnetoelectric effect. Fermi energy tuning plays a role in inducing phase transitions and developing future device functions. Here, we report on controlling the topological phases in a dual-gate field-effect transistor of a semi-magnetic topological insulator heterostructure. The heterostructure consists of magnetized one-surface and non-magnetic other-surface. By tuning the Fermi energy to the energy gap of the magnetized surface, the Hall conductivity σxy becomes close to the half-integer quantized Hall conductivity e2/2h, exemplifying parity anomaly. The dual-gate control enables the band structure alignment to the two quantum Hall states with σxy = e2/h and 0 under a strong magnetic field. These states are topologically equivalent to the QAH and axion insulator states, respectively. Precise and independent control of the band alignment of the top and bottom surfaces successively induces various topological phase transitions among the QAH, axion insulator, and parity anomaly states in magnetic topological insulators.

Relationship of Chronic Ankle Instability With Foot Alignment and Dynamic Postural Stability in Adolescent Competitive Athletes.

Competitive adolescent athletes should be aware of the early signs of chronic ankle instability (CAI) and the connection between the condition and performance. To investigate whether CAI is related to foot alignment and morphology as well as dynamic postural stability after a jump landing among adolescent competitive athletes with and without a history of a lateral ankle sprain and CAI. Cross-sectional study; Level of evidence, 3. Between July 2020 and August 2021, adolescent competitive athletes (N = 85; n = 49 boys; n = 36 girls) were classified into 3 groups using Cumberland Ankle Instability Tool (CAIT) scores: healthy athletes (n = 55), coper athletes (n = 19), and athletes with CAI (n = 11). Results of foot alignment assessments involving the leg-heel angle (LHA) and navicular height, intrinsic foot muscle morphology, dynamic postural stability index (DPSI), and other parameters were compared among the 3 groups. The relationship between the CAIT score and the LHA and dynamic postural stability and instability were examined using multiple linear regression. Compared with the healthy group, the CAI group had a significantly greater LHA (8.73°± 3.22° vs 6.09°± 3.26°; P < .05), higher DPSI (0.336 ± 0.046 vs 0.298 ± 0.035), and higher vertical stability index (0.303 ± 0.048 vs 0.264 ± 0.037; P < .05 for all). Multiple regression analysis showed that the LHA (β = -0.228; P = .033) and DPSI (β = -0.240; P = .025) were significantly associated with the CAIT score . Valgus rearfoot alignment and poorer dynamic postural control were associated with CAI among adolescent athletes.

Automated Hooking of Biomedical Microelectrode Guided by Intelligent Microscopic Vision

Biomedical microelectrode implantation is a promising approach to achieve invasive brain-machine interface with high bandwidth and good biocompatibility. However, it is difficult to manipulate a microelectrode probe because of its micron-level width and flexible material. Toward the challenging robotic implantation, this article addresses an essential operation step: automated hooking of flexible microelectrode probe with a micro-needle. First, a point-contour of interest extraction network for microscopic image (MicroPCIE) is proposed to obtain key image features for visual guidance. Based on few-shot learning mechanism, MicroPCIE trained on nonspecific dataset can be rapidly deployed to the specific hooking task without requiring data-driven optimization. Second, a robotic hooking control system is designed considering the distributed probe locations, variable needle direction, and efficiency requirements. The needle-probe alignment control is executed under low and high microscope magnifications, to realize larger operation range and permit high alignment precision. The optical design and camera aiming control are proposed to guarantee the visibility and clearness of objects after low-to-high magnification switch. The effectiveness of the proposed methods is validated with a series of experiments.

Surface termination control of charge transfer and band alignment across a semiconductor–crystalline-oxide heterojunction

Surface termination control of charge transfer and band alignment across a semiconductor–crystalline-oxide heterojunction

3D laser scanning for predicting the alignment of large-span segmental precast assembled concrete cable-stayed bridges

Reasonable alignment control can simplify the bridge construction process, reduce the complexity and cost of construction, and improve construction efficiency. The prefabricated assembling construction method brings challenges to alignment control. This study proposes a method for predicting the alignment of concrete cable-stayed bridge assemblies in unstressed conditions to accelerate the construction process. The method uses the target paper to identify the 3D coordinates of control points and a coarse-to-accurate alignment method to achieve the virtual preassembly of precast concrete sections. The effectiveness of the method is demonstrated by comparing the errors in key parameters between virtual and physical preassembly and the predicted alignment results obtained through 3D coordinate conversion with the designed precast alignment. The method was applied to the construction of a large-span concrete cable-stayed bridge for a high-speed railroad in Guangdong, China, and the construction period was shortened by about 42 days.

Utilization of Physical Anisotropy in Metal-Organic Frameworks via Post-Synthetic Alignment Control with Liquid Crystal.

Metal-organic frameworks (MOFs) represent crystalline materials constructed from combinations of metal and organic units to often yield anisotropic porous structures and physical properties. Postsynthetic methods to align the MOF crystals in bulk remain scarce yet tremendously important to fully utilize their structure-driven intrinsic properties. Herein, we present an unprecedented composite of liquid crystals (LCs) and MOFs and demonstrate the use of nematic LCs to dynamically control the orientation of MOF crystals with exceptional order parameters (as high as 0.965). Unique patterns formed through a facile multidirectional alignment of MOF crystals exhibit polarized fluorescence with the fluorescence intensity of a pattern dependent on the angle of a polarizer, offering potential use in various optical applications such as an optical security label. Further, the alignment mechanism indicates that the method is applicable to numerous combinations of MOFs and LCs, which include UV polymerizable LC monomers used to fabricate free-standing composite films.

Cell patterning on photocrosslinkable polymer films with micropatternable surfaces

AbstractThe regulation of cell behavior is crucial for understanding many fundamental biological processes and designing novel medical devices. Nano/micropatterning has been developed as a means of controlling cellular properties and behaviors. Using cinnamoyl groups that have undergone photodimerization, we have prepared facile photopatterning films with adjustable surface properties for cell patterning via simple steps. Our strategy for controlling surface properties uses the decrease in free volume induced by photocrosslinking. This paper describes the surface‐patterning properties of photocrosslinkable polymer films and the cell adhesion to their micropatterned surfaces. Upon culturing cells on micropatterned surfaces, preferential cell adhesion, alignment and proliferation are observed in the unexposed regions. Additionally, diverse surface patterns of photocrosslinkable polymer films have been fabricated using various photomasks, enabling effective control of cell adhesion and alignment. The ability to regulate cellular behavior via microfabricated surfaces of photocrosslinkable polymer films enables a new and facile approach for designing scaffolds for the development of novel advanced materials, tissue engineering, and regenerative medicine.

Directed alignment of graphene-oxide liquid crystals in confined spaces: Effects of flow, pickering stabilization, and phase transition

Because of its versatility for processing, graphene oxide (GO) serves as a superior substance for two-dimensional carbon-based materials. Controlling GO alignment is crucial to augment its inherent anisotropic nature. Here, we report the controlled alignment of GO confined in the rectangular and circular capillary tubes. GO aligns in contrasting orientations according to the phase of GO dispersion during loading into a capillary. Upon GO liquid crystal (LC) loading, GO-layers are oriented tangential to the inner surface of capillary, resulting in a concentric organization of the GO-layers. In the LC phase, the GO orientation is mainly influenced by the flow so that the GOs are aligned tangential to the hydraulic shear plane. However, GO self-assembles parallel to the capillary cross-section when loaded in the isotropic phase and then concentrated into the LC phase. Surprisingly, by excluding flow-induced effects, the GO layer is aligned perpendicular to the inner surface throughout the capillary. This unexpected alignment of the GO-layers is initiated in the meniscus region by the “Pickering effect” (i.e., tangential adsorption of GO along the Air-Liquid interface). Upon solvent evaporation, GO dispersions experience a sequential isotropic to nematic phase transition from the meniscus to the central region. During the phase transition, the orientation of the GO layer is determined by the long-range ordering of the LC phase. As a result, the alignment effect caused by the Air-Liquid interface determines the GO alignment throughout the capillary. Our results provide useful insight into the delicate control of GO alignment in a confined space. Precise control of GO alignment in a confined space can be achieved based on the appropriate directional design of the Air-Liquid interface and the corresponding sequential phase transition.

Inertial Stable Platforms for Precision Pointing of Optical Systems in Aerospace Applications

Both airborne and space-based high-energy laser weapon systems present interesting challenges for precision line-of-sight control. Sub-microradian to microradian pointing accuracies are required against dynamic targets. In addition, “absolute” pointing and accurate inertial angular rate measurement are required to support mission requirements. This paper addresses these unique directed-energy weapon (DEW) precision-pointing requirements and their associated implementation alternatives in the context of strapdown and stable platform inertial reference technologies. The contributions of this paper consider the broader issues of DEW requirement drivers, integration of the stabilization system with the rest of the optical system, and design tradeoffs between stable platform and strapdown stabilization mechanizations. Both types of mechanisms are mounted to the gimbal of an imaging system using gryo sensors (gyros) and accelerometers to maintain a desired orientation in inertial space independent of the craft motion. Although both can include an optical reference that propagates through the optical path for optical alignment and jitter control, only in the stable platform is the optical reference stabilized. When combined on the same platform with a stabilized inertial measurement system and closed-loop stabilization with the optical reference, the mechanism becomes a stabilized inertial reference unit, which provides a stabilized optical reference to the electro-optical/laser pointing and jitter control systems.

Structure-induced Intelligence of Liquid Crystal Elastomers.

Liquid crystal elastomers (LCEs) are active soft matter-based materials with strong stimulus responsiveness and reversible, large-shape morphing capabilities. LCEs have demonstrated broad and growing applications in soft robotics, wearable devices, artificial muscles, and optical machines. The actuation intelligence and advanced functionality of LCEs depend on the smartness and properties of structures. In this review, we discuss recent advances in structure-induced intelligence of LCEs, specifically the integration of structural properties with the alignment and processing of LCEs. The structural design principles for three categories consisting of common structures (film, fiber, and tubule), smart structures (origami, kirigami, mechanical metamaterial, topology, and topography), and complex structures (monolithic and integrated) are presented. Various alignment controls of LCEs, including mechanical, surface, field-assisted, and shear alignment, are capable of inducing structural properties. The coupling and collaboration mechanisms of the LCE structures and the generated functions are discussed. The review concludes with perspectives on current challenges and emerging opportunities.

Hybrid Piezoelectric–Magnetic Self‐Sensing Actuator using Novel Dual‐Alignment Magnetic/Mechanical Processing for Vibration Control of Whole‐Body Vibrations

Multi‐stimuli‐responsive/‐functional polymeric materials can respond to numerous stimuli and execute multiple tasks, overcoming barriers faced by single‐stimuli materials. Herein, the development of hybrid piezoelectric–magnetic self‐sensing actuator (HPMSA) that can both sense and actuate is proposed. This iron oxide/functionalized carbon nanotube/polyvinylidene fluoride film optimizes both piezoelectric and magnetic properties through dual‐alignment fabrication, utilizing strong element bonds for simultaneous alignment. Magnetic nanoparticles are advantageous over nanorods due to latter's randomized shape anisotropy decreasing magnetization. The dual magnetic and mechanical processing increases polar β‐crystal content to 88%, where magnetic alignment alone increases degree of crystallinity to 66%. As a vibration damper, HPMSA operates within 40–600 Hz frequency, with a sensing sensitivity of 2.5 mV g−1 and 0.72 m s−2 weighted acceleration damping, lowering passenger health risks. Piezoelectric and magnetic relationship shows 0.19 V increase with 125 mT applied. The flexible HPMSA can integrate onto a curved surface and sense/dampen vibrations of an air motor, propeller drone, and simulated tremors. The HPMSA provides tremendous potential and understanding into multi‐stimuli‐responsive/functional materials, simultaneous alignment, and vibration control in the next generation of transportation vehicles for human safety.

Collective bending motion of a two-dimensionally correlated bowl-stacked columnar liquid crystalline assembly under a shear force.

Stacked teacups inspired the idea that columnar assemblies of stacked bowl-shaped molecules may exhibit a unique dynamic behavior, unlike usual assemblies of planar disc- and rod-shaped molecules. On the basis of the molecular design concept for creating higher-order discotic liquid crystals, found in our group, we synthesized a sumanene derivative with octyloxycarbonyl side chains. This molecule forms an ordered hexagonal columnar mesophase, but unexpectedly, the columnar assembly is very soft, similar to sugar syrup. It displays, upon application of a shear force on solid substrates, a flexible bending motion with continuous angle variations of bowl-stacked columns while preserving the two-dimensional hexagonal order. In general, alignment control of higher-order liquid crystals is difficult to achieve due to their high viscosity. The present system that brings together higher structural order and mechanical softness will spark interest in bowl-shaped molecules as a component for developing higher-order liquid crystals with unique mechanical and stimuli-responsive properties.

A real-time shaft alignment monitoring method adapting to ship hull deformation for marine propulsion system

Shaft alignment states are strictly stipulated in the marine propulsion system. However, there are relatively limited studies on shaft alignment monitoring and control considering the effects of ship hull deformation (SHD). SHD can be caused by wave load, loading, depth, speed, etc., and leads to various relative displacements at different shaft supporting points between the ship foundation and the support bearings of the propulsion system. It leads to shaft misalignment, increases shaft vibration and noise, and even endangers the safety of shaft system during the operation stages. To overcome this problem, a real-time shaft alignment monitoring method based on laser displacement sensors (SAMM/LDS) is proposed. Firstly, the defects of a present shaft alignment monitoring method based on eddy current displacement sensors (SAMM/ECDS) are analyzed when considering the effects of SHD. The structure and working principle of a shaft alignment monitoring system adapted to SHD (SAMS/SHD) are proposed. It consists of three sub-systems: the shaft alignment monitoring sub-system adapting to SHD (SAMSS/SHD), the present shaft alignment monitoring sub-system (SAMSS/P), and the shaft alignment correcting sub-system (SACSS). Based on SHD data-driven, SAMS/SHD can not only take advantage of SAMSS/P for long-time operations but also reflect SHD by exploiting the advantages of SAMSS/SHD. Secondly, SAMM/LDS is deduced. Two laser displacement sensors (LDS) are placed on the driving shaft and the driven shaft to reflect the spatial relative displacement and attitude information affected by SHD. Therefore, two reference coordinate systems are fixed at the center of LDS, and the coordinate expressions of their imaging points are derived using a 4 × 4 homogeneous coordinate transformation matrix. For reducing computing complexity in engineering applications, a simplified monitoring model is proposed for very small rigid-body rotational angularities. Finally, the effectiveness and testing accuracy of the SAMM/LDS is verified on a five-DOF platform which can simulate the effects of SHD. The SAMM/LDS can be used to realize real-time and high-precision shaft alignment monitoring for marine propulsion system which can adapt to the effects of SHD and so on. Based on the foundation of this research, compensation control algorithms to solve the misalignment effects deduced by SHD will be studied for marine propulsion system with resilient mounts in the next few years.

Alignment control of self-assembling Si quantum dots

We have demonstrated the formation of one-dimensionally aligned self-assembling silicon quantum dots (Si-QDs) by low-pressure (LP) CVD using pure monosilane (SiH4) gas. Formation of Si-QDs on line-patterned SiO2 formed on p-Si(100) after low-temperature oxidation was carried out. From AFM images taken after LPCVD, we confirmed high-density Si-QDs formation with an areal density as high as ∼1011 cm−2 on the OH-terminated SiO2-line while dot density as low as ∼1010 cm−2 on as-grown SiO2. We also confirmed that, with a decreasing the SiO2 line width, the number of Si-QDs on the SiO2-line was decreased evidently. Based on the results, we have succeeded in the one-dimensional arrangement of Si-QDs on the ∼30 nm-width SiO2 line-patterns.

Short-term clinical results with a trifocal diffractive toric intraocular lens using an optimized preoperative and intraoperative protocol.

To evaluate the short-term clinical outcomes of a specific toric diffractive trifocal intraocular lens (IOL) implanted following an optimized clinical protocol in a large population. Retrospective analysis of 337 eyes of 231 patients (mean age, 62.2 years) undergoing cataract surgery with implantation of the trifocal diffractive IOL AT.LISA tri toric 939M/MP (Carl Zeiss Meditec). A strict and careful clinical protocol was followed, including an accurate measurement of corneal astigmatism, use of a latest generation IOL power calculator, photography-based method intraoperative control of IOL alignment and IOL reposition at 1 week postoperatively if needed. Clinical outcomes in terms of visual acuity, refraction, efficacy of astigmatic correction analysed by vector analysis and patient satisfaction were evaluated during a 3-month follow-up. A total of 82% and 98% of eyes achieved a postoperative uncorrected distance visual acuity of 0.00 and 0.10 logMAR or better, respectively. Furthermore, 99.7%, and 100.0% of eyes showed a postoperative spherical equivalent within ± 0.50 D and ± 1.00 D, with 97.9% of eyes having a postoperative cylinder ≤ 0.50 D. Uncorrected near and intermediate visual acuities were 0.2 logMAR or better in 89.0% and 99.1% of eyes, respectively. Mean difference vector, magnitude of error and angle of error were 0.02 ± 0.14 D, 0.02 ± 0.13 D and 0.11 ± 1.18°. Patient satisfaction was referred as high or very high by 97.6% of patients. The implantation of the trifocal toric IOL evaluated following a careful clinical protocol provides an efficacious visual rehabilitation and astigmatic correction, leading to high levels of patient satisfaction.